Telescopic Module

ABSTRACT

A telescopic module, which may be incorporated in a desk or a chair to elevate or lower a worksurface, includes a first tube, second tube, and a plurality of rollers. The first tube has a passageway, in which the second tube is received for reciprocation. The rollers are pivoted on the second tube or the first tube, or both to touch an inner side of the first tube and an outer side of the second tube to be turned when the second tube is moving. The rollers may reduce the friction between the first and the second tubes when the second tube is moving.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional application of U.S. application Ser. No. 15/664,598, filed on Jul. 31, 2017, the entire disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Technical Field

The present invention relates to a desk or a chair, and more particularly to a telescopic module of a desk or a chair for elevating and lowering a worksurface.

2. Description of Related Art

Typically, a conventional desk has a consistent height of a worksurface, and a user may sit on a chair to read, write, or operate a computer on the desk. However, heights of people are different, so that the desk and chair with a consistent height can't meet all heights of the users.

An improved desk has a telescopic stand to adjust its height. The conventional telescopic stand has an inner tube and an outer tube to elevate or lower the worksurface by moving the inner tube, and fix the inner tube to the outer tube when the telescopic stand is adjusted to a desired length. The same structure of the telescopic stand may be incorporated in a chair.

It is easy to understand that a friction is occurred between the inner tube and the outer tube when the telescopic stand is telescoped. In order to reduce the friction, a ring is provided between the inner tube and the outer tube. Typically, the ring is fixed to the outer tube, so there still is a relative motion between the ring and the inner tube. It may wear the ring, and make it lose the function of reducing the friction. The worn ring causes an unstable telescoping motion of the telescopic stand as well.

An improved telescopic stand is provided with ribs on an inner side of the outer tube or an outer side of the inner tube instead of the ring. The ribs may reduce the friction between the inner tube and the outer tube. However, the inner tube and the outer tube still will be worn after a long time of operation.

BRIEF SUMMARY OF THE INVENTION

In view of the above, the primary objective of the present invention is to provide a telescopic module, which has a small friction and a stable movement when the telescopic module is elevated or lowered.

The secondary objective of the present invention is to provide a telescopic module, which may reduce the wear of the elements of the telescopic module.

In order to achieve the objective of the present invention, a telescopic module includes a first tube, second tube, and a roller between the first and the second tube. The first tube has a passageway, in which the second tube is received for reciprocation. The roller touches at least one of an inner side of the first tube and an outer side of the second tube to be turned when the second tube is moving.

The roller may reduce the friction between the first and the second tubes when the second tube is moving.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which

FIG. 1 is a sectional view of a first preferred embodiment of the present invention;

FIG. 2 is a sectional view of the first preferred embodiment of the present invention, showing the telescopic module telescoping;

FIG. 3 is a sectional view of a second preferred embodiment of the present invention, showing the first leg member be lowered;

FIG. 4 is a sectional view of the second preferred embodiment of the present invention, showing the telescopic module telescoping;

FIG. 5 is a perspective view of a third preferred embodiment of the present invention;

FIG. 6 is a partial sectional view of the third preferred embodiment of the present invention;

FIG. 7 is a perspective view of a fourth preferred embodiment of the present invention, showing the first leg member be lowered;

FIG. 8 is a partial sectional view of the fourth preferred embodiment of the present invention;

FIG. 9 is a perspective view of the hub and the adjusting member of a preferred embodiment of the present invention;

FIG. 10 is a perspective view of another adjusting member of a preferred embodiment of the present invention;

FIG. 11 is a partial sectional view of a fifth preferred embodiment of the present invention; and

FIG. 12 is a perspective view of the hub and alternate rollers of a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 and FIG. 2 show a telescopic module of the first preferred embodiment of the present invention, which is connected to a worksurface 10 to adjust a height of the worksurface 10. The telescopic module may be incorporated into a desk, a chair, or any other devices which is able to elevate and lower the worksurface 10. It is noted that usually there are a plurality of the telescopic modules are incorporated.

The telescopic module of the first preferred embodiment of the present invention includes a first tube 20 and a second tube 30. The first tube 20 has a passageway 22, in which the second tube 30 is received for free reciprocation. A plurality of rollers 40 are pivoted on the first tube 20 and touch the second tube 30.

The first and the second tubes 20, 30 are rectangular tubes. Four of the rollers 40 are pivoted on four sides of the first tube 20 to touch four outer sides 32 of the second tube 30.

The second tube 30 is moved relative to the first tube 20 to adjust the height of the worksurface 10, and the rollers 40 may reduce a friction when the second tube 30 is moving and provide the second tube 30 with a stable movement.

As shown in FIG. 3 and FIG. 4, the second preferred embodiment of the present invention provides four rollers 40 on the second tube 30 to touch four inner sides 24 of the first tube 20.

The second preferred provides the same function of reduction of friction and wear of the tubes when the second tube 30 is moving.

As shown in FIG. 5 and FIG. 6, a telescopic module of the third preferred embodiment of the present invention further provides a hub 50 on an end 26 of the first tube 20, and the rollers 40 are pivoted on an inner side of the hub 50 to touch the second tube 30, which is inserted into both the hub 50 and the first tube 20. The function of the third preferred embodiment are the same as above, including reduction of friction and wear, and providing the second tube 30 a stable movement.

As shown in FIG. 7 and FIG. 8, a telescopic module of the fourth preferred embodiment of the present invention further provides a hub 60 on an end 34 of the second tube 30, and the rollers 40 are pivoted on the hub 60 to touch the first tube 20.

As shown in FIG. 9, the hub 60 includes an engaging portion 62 and an extending portion 64 connected to the engaging portion 62. A diameter of the engaging portion 62 is smaller than that of the extending portion 64. The hub 60 is provided with a slot 63 between the engaging portion 62 and the extending portion 64.

The hub 60 is provided with an expanding hole 66 extending from the extending portion 64 to the engaging portion 62 and a threaded hole (not shown) at an inner end of the expanding hole 66. A diameter of the expanding hole 66 gradually narrows from the extending portion 64 to the engaging portion 62, so that there is a conical sidewall 68 surrounding the expanding hole 66. The hub 60 further is provided with several gaps 70 to form a plurality of flexible portions 72 between the gaps 70. The rollers 40 each has opposite ends connected to two of the neighboring flexible portions 72.

The telescopic module 80 further includes an adjusting member 80, having a conical head 82 and a threaded section 84. The cone head 82 is complementary to the conical sidewall 68, and is slightly bigger than the conical sidewall 68.

As shown in FIG. 8, the engaging portion 62 of the hub 60 is inserted into the second tube 30, and the extending portion 64 is left out to let the rollers 40 touch the inner side 24 of the first tube 20.

The adjusting member 80 is screwed into the expanding hole 66 with the threaded section 84 engaging the threaded hole and the conical head 82 abutting against the conical sidewall 68 to move the flexible portions 72 outwardly as well as the rollers 40 connected to the flexible portions 72 while the adjusting member 80 is being turned. The deeper the adjusting member 80 is screwed, the further the flexible portions 72 move. As a result, pressures of the rollers 40 against the inner side 24 of the first tube 20 are adjustable by turning the adjusting member 80. Therefore, it may provide the second tube 30 a more stable and smoother movement, and minimum the friction when the second tube 30 is moving by turning the adjusting member 80 even if the telescopic module is operated for a long time.

As shown in FIG. 9, the adjusting member 80 is provided with a connecting portion 86. The connecting portion 86 is a slot configured to connect a driving device (not shown), such as a hand tool and a power tool, for a user easier to turn the adjusting member 80 by operating the driving device.

The adjusting member 80 is provided with a bore 88, which is configured to connect a pneumatic device (not shown) to elevate or lower the telescopic module powered by the pneumatic device.

As shown in FIG. 10, the connecting portion 86 is a block projected from the adjusting member 80 configured to connect a barrel of a driving device (not shown), and the block is provided with a bore 88 configured to connect a pneumatic device (not shown). The function of the connecting portion 86 and the bore 88 are the same as above.

As shown in FIG. 11, two hubs 50, 60 are provided in the telescopic module of the fifth preferred embodiment of the present invention, one of which 50 is connected to the first tube 20 with rollers 40 against the second tube 30, and the other of which 60 is connected to the second tube 30 with rollers 40 against the first tube 20. It has the same function as above.

In the above preferred embodiment, the rollers 40 are cylindrical rollers, and they may be ball rollers as well (FIG. 12).

It must be pointed out that the embodiments described above are only some preferred embodiments of the present invention. All equivalent structures which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention. 

What is claimed is:
 1. A telescopic module, comprising: a first tube having a passageway therein; a second tube received in the passageway of the first tube for reciprocation; and a hub, on which a roller is pivoted, wherein the hub is connected an end of the first tube with the roller touching an outer side of the second tube, and the roller is turned when the second tube is moved related to the first tube.
 2. The telescopic module of claim 1, wherein the roller is covered neither by the first tube nor by the second tube.
 3. The telescopic module of claim 1, wherein the hub has a portion attached to an outer side of the first tube.
 4. The telescopic module of claim 1, wherein the hub has a portion against the end of the first tube, on which the roller is pivoted. 